by E. Cornehus. 325 



with which it is associated, and which is so troublesome to the 

 feet of horses. The soil consists of a soft clay, or Ught sand, 

 on which you seldom meet with a stone of any kind. The 

 surface of the earth is undulating and hilly, but not mountain- 

 ous. The water-courses do not move rapidly and tumultu- 

 ously, as in the limestone country ; but form in the soft earth, 

 deep trenches, through which they ghde smoothly and silently 

 along. The smallest rivulet often has a trench ten feet deep ; 

 and the earth over which it passes, is continually yielding to 

 its gentle attrition. 



The only minerals which I observed, are sandstone, common 

 and ferruginous ; silicious pebbles in beds of creeks, and oc- 

 casionally on the uplands ; earthy ores of iron, particularly 

 red oxides, and petrifactions of shells, wood, &c. In addition 

 to these, it may here be mentioned that galena has been found 

 in small quantities at Gibson's Port, and at Ellis's Cliffs, in the 

 State of Mississippi : a crystal of amethyst, in the same state, 

 by Mr. Blannerhassett ; and a great variety of useful ochres, 

 in many places on the banks of the Mississippi. 



In the geological map attached to Professor Cleaveland's Mi- 

 neralogy, the alluvial country bordering on the Gulf of Mexico, 

 is represented as terminating at Natchez. But why its termi- 

 nation is placed here, I am unable to understand. The country 

 above and below Natchez, so far as it has come under my ob- 

 servation, presents no difference of appearance in its geology, 

 or mineralogy. I am aware that at Natchez, when the water 

 of the Mississippi is lowest, a soft rock is seen, from which 

 lime has been obtained. But this rock is two hundred feet 

 below the surface of the adjoining country ; and admitting that 

 it is a limestone rock, there is no difficulty in supposing it may 

 constitute the basis of the alluvial deposit which rests upon it. 

 That the incumbent earth is alluvial, can be doubted, I think, 

 by no one who has had an opportunity of examining it. By 

 means of a road, which has been cut obhquely down the side 

 of the bluff, distinct layers of clay, sand, and pebbles, have 

 been exposed for the whole distance from the summit to the 

 base. The same character is observed at a distance from the 

 river, where the earth has been excavated by washing, or dig- 



